This invention is for apparatus for the sustained injection of liquid intravenously, as distinguished from a quick shot from a hypodermic needle, and is for an apparatus for this purpose that is less cumbersome and more convenient than the gravity method presently in use where a plastic flask, formerly a bottle, is suspended from an elevated hook at a level well above the patient and the liquid flows by gravity from the flask through a long flexible plastic tube, on the free end of which is a discharge terminal either in the nature of a needle or catheter entered into a patient's vein, usually but not necessarily in the forearm.
The most common means for suspending the flask comprises a metal pole on a base provided with casters to enable it to be rolled about the room and hallway and which generally has one or more radially extending arms at the top. Each arm has a hook at the end from one of which a plastic flask containing the liquid to be injected is hung.
This post arrangement is quite heavy, the base being weighted so that the post will not easily tip over. If the patient has to be moved, this pole must go along with him; it must be maneuvered around when the room is being cleaned or when the patient is being transferred from a bed to a chair or another bed.
Many patients could desirably be mobile and free to ambulate through the corridor or to a lounge or to travel back and forth to the bathroom except for the limitation against freedom of movement imposed by the need to pull, or have an attendant pull, the pole and suspended flask whenever he moves. Trips in the elevator to X-ray or other diagnostic equipment are likewise often hampered by this need to keep the pole and suspended flask close to the patient. There is the ever present risk of the long hose between the flask and the patient becoming caught or hung up on a doorknob or other protruding object, sometimes resulting in a painful flesh wound where the discharge terminal is pulled from the patient's vein.
Various attempts have heretofore been made to dispense with the gravity method of injecting the liquid, but so far as we are aware, they have required specially shaped bags of cumbersome shape and have been quite unacceptable.